1. Field of the Invention
The present invention relates to a method for transmitting and receiving informations of control plane using MAC (medium access control) frame structure in order to transmit user data through an associated control channel so that the radio resource formed between a mobile station and a base station can be used efficiently, in the case that the third generation mobile communication system which needs large scale control information necessarily uses out-of-band signal method for providing various services.
2. Description of the Related Art
As the third generation mobile communication service such as ITM-2000 (International Mobile Telecommunication-2000) provides various services, the quantity of signal transmitted between the mobile station and the base station is increased considerably compared with that of prior mobile communication system, and accordingly it is desirable to set a dedicated control channel in addition to a traffic channel for maintaining the quality of traffic and providing various services. The signal transmission method described above is called out-of-band signal method. The out-of-band signal method is a signal transmission method in which an associated control channel and more than one traffic channel are assigned and other mobile station can not use them after a call is set and until a call is cancelled. Therefore, if the user informations can be transmitted using the channel which is not used frequently after setting a call, the radio resource can be used efficiently and the services can be provided to more users.
The IS-95 Code Division Multiple Access (CDMA) digital mobile communication system is a system for voice communication mainly, so it does not have much signal traffic. Accordingly, when a signal traffic needs to be transmitted, the system adopts the method that the quality of voice traffic is deteriorated to some extent. That is, when the signal needs to be transmitted, the signal was transmitted using the traffic channel only without separating the signal channel from traffic channel. Such signal transmission method is called in-band signal transmission method. However, this method could not satisfy user's service requirements since user requires various and high quality services. The various and high quality services require more signal traffics compared with simple services relatively, and the Quality Of Service (QOS) of user data is deteriorated and delay of signal traffic transmission occurs when signals are to be transmitted in the in-band method. This problem can be solved by transmitting the signal traffics using other channel different from user data transmission channel. This is called out-of-band signal transmission method.
In the signal channel setting method of mobile station and base station, the out-of-band signal transmission method requires more control channels than that of in-band signal transmission method. Also, the informations transmitted through control channel usually occur at the time of call setting and cancelling and have low frequency in use compared with traffic channel. Accordingly, in mobile communication, the control channel having low frequency in use not only causes waste of radio resource but deteriorates capacity and performance of system.